Carrier / Infinity 27
Carrier Infinity 27 33k R-454B 208/230V Mini-Split
The largest Infinity 27, a roughly 3-ton 230V head on R-454B, rated 19.6 SEER2, 12 EER2, and 10.5 HSPF2. Heating is substantial: 36,000 BTU at 47F, 30,000 BTU at 17F, and 35,000 BTU at 5F. It is ENERGY STAR certified and cold-climate designated.
1 zoneProfessional installCurrent
Refrigerant generation
R-454B - current-generation refrigerant
Image: Carrier
Data completeness: 100%
- Last sourced
- Jul 27, 2026
SplitAtlas score
8.7 / 10
Cooling efficiencyBelow average
(19.6 SEER2) among 36k systems
Heating efficiencyTop quartile
(10.5 HSPF2) among 36k systems
Cold-weather performanceTop quartile
(97.2% heat retained at 5F) among 36k systems
WarrantyAbove average
(10 yr parts / 10 yr compressor) across the catalogue
Feature setAbove average
(6 verified features) across the catalogue
Documentation & partsBelow average
(6 manuals; spec sheet) across the catalogue
Not evaluated
- Installation accessibility — not applicable (professional install)N/A
professional install - DIY-accessibility not applicable
- Price-to-value — not evaluatedN/A
quote-only - no retail price to evaluate
Key ratings
Buyer review snapshot
Install difficulty
Professional install
- Electrical: 230V.
Availability and price context
- Warranty warning: Warranty coverage does not apply to any product purchased over the Internet. Online listing: $5,774.99 at HVACDirect; checked Jul 27, 2026; price source is HVACDirect.
Purchase channel policy
Carrier's ductless warranty excludes products purchased over the Internet; buyers should treat public online carts as outside the warranty-covered purchase channel.
- Warranty consequence
- Warranty coverage does not apply to any product purchased over the Internet.
- Authorized channel
- Licensed HVAC technician installation with defective parts returned to the distributor through a registered servicing dealer; not an internet purchase.
Any online offer for this brand should be treated as a warranty-risk warning, not a recommendation.
Compare online-purchase warranty rules by brand
Source: Carrier Corporation: CAC/BDP Limited Warranty Certificate - Limited Warranty for Ductless Split Units; retrieved Aug 15, 2026.
Source date
- Model data sourced
- Jul 27, 2026
- Page reviewed
- Jul 27, 2026
- Source-backed records
- 4
- Newest source retrieved
- Jul 27, 2026
Warranty tiers
Warranty: 10 years parts and no separate compressor term published as standard.
Model context
- Structured ratings
- Certification: ENERGY STAR certified and AHRI cold-climate designated. Refrigerant: current low-GWP R-454B.
Strengths
- Enormous cold-weather heat, delivering 35,000 BTU at 5F, near its 47F output, a standout cold-climate result.
- Cold-climate and ENERGY STAR certified at a large capacity, with Carrier's premium warranty support.
Weaknesses
- SEER2 of 19.6 is the lowest in the Infinity 27 range, so cooling efficiency is modest for the price.
- Large 230V system sized well beyond a single room.
Climate suitability
- Minimum heating ambient
- No model-specific value is published on the current Carrier consumer listing
- Rated heating at 5F
- 35,000 BTU/h[2]
- Rated heating at 17F
- 30,000 BTU/h[2]
- Rated heating at 47F
- 36,000 BTU/h[2]
Specifications
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- Manufacturer
- Carrier
- Brand
- Carrier
- Product line
- Infinity 27
- Model number
- 45MAHAQ33XA3 indoor / 37MAHAQ33AA3 outdoor
- Indoor unit model
- 45MAHAQ33XA3
- Outdoor unit model
- 37MAHAQ33AA3
- Number of zones
- 1
- Max indoor units
- not published
- Rated cooling capacity
- 33,000 BTU/h[2]
- Rated heating capacity
- 36,000 BTU/h[2]
- Voltage
- 230 V[1]
- MCA
- No model-specific value is published on the current Carrier consumer listing
- Maximum fuse or breaker size
- No model-specific value is published on the current Carrier consumer listing
- Breaker needed
- not published
- SEER2
- 19.6 SEER2[2]
- EER2
- 12 EER2[2]
- HSPF2 (Region 4)
- 10.5 HSPF2[2]
- HSPF2 (Region 5)
- not published
- COP
- not published
- COP at 47F
- not published
- COP at 5F
- 1.98 COP[2]
- Minimum outdoor heating temperature
- No model-specific value is published on the current Carrier consumer listing
- Minimum outdoor cooling temperature
- No model-specific value is published on the current Carrier consumer listing
- Maximum outdoor temperature
- No model-specific value is published on the current Carrier consumer listing
- Indoor noise range
- No model-specific value is published on the current Carrier consumer listing
- Outdoor noise rating
- No model-specific value is published on the current Carrier consumer listing
- Indoor weight
- No model-specific value is published on the current Carrier consumer listing
- Outdoor weight
- No model-specific value is published on the current Carrier consumer listing
- Refrigerant
- R-454B[2]
- Refrigerant charge
- not published
- Manufacturer coverage
- not published
- Line-set size
- No model-specific value is published on the current Carrier consumer listing liquid / No model-specific value is published on the current Carrier consumer listing suction
- Included line-set length
- Professional installations use separately selected line sets
- Maximum line-set length
- No model-specific value is published on the current Carrier consumer listing
- Max line set per indoor
- not published
- Maximum elevation difference
- No model-specific value is published on the current Carrier consumer listing
- Max height between indoor units
- not published
- Wi-Fi support
- No model-specific value is published on the current Carrier consumer listing
- Energy Star status
- ENERGY STAR certified[3]
- AHRI certification number
- 215323747[2]
- Warranty
- Standard: 10 yr parts / no separate compressor term (eligible timely registered residential installation). Consumer Choice Warranty: 10-year parts-only or 5-year parts plus 3-year labor for eligible timely registered residential installations; terms and participating dealer requirements apply.
- Install path
- Professional install
- Retail price
- online listing with warranty risk: $5,774.99
- Available retailers
- HVACDirect
- Manual links
- AHRI public directory record 215323747, ENERGY STAR exact check 215323747, Infinity 27 installation documentation locator, Carrier Infinity 27 Mini Split Heat Pump, HVACDirect exact Carrier affiliate offer carrier-infinity-27-33k-r454b-230v, AHRI Appendix M1 public detail 215323747
- Specification sheet
- AHRI Appendix M1 public detail 215323747
- Last sourced date
- Jul 27, 2026
Retail purchase context
Warranty consequence
Warranty coverage does not apply to any product purchased over the Internet.
Any online offer for this brand should be treated as a warranty-risk warning, not a recommendation.
Authorized channel: Licensed HVAC technician installation with defective parts returned to the distributor through a registered servicing dealer; not an internet purchase.
Some retailer links may earn us a commission at no extra cost; paid relationships never change scores or recommendations. Affiliate disclosure
Paid link
Warranty-risk online listing
Listed at HVACDirect: $5,775. Checked Jul 27, 2026; price source HVACDirect.
Electrical requirements
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- Voltage
- 230 V[1]
- Voltage range
- 208/230V[1]
- Phase
- 1[1]
- Frequency
- 60 Hz[1]
- MCA
- No model-specific value is published on the current Carrier consumer listing
- Breaker needed
- not published
- Maximum breaker size
- No model-specific value is published on the current Carrier consumer listing
- Maximum fuse size
- No model-specific value is published on the current Carrier consumer listing
- Maximum cooling current
- not published
- Maximum heating current
- not published
- Manufacturer wire notes
- not published
Installation considerations
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- Liquid line
- No model-specific value is published on the current Carrier consumer listing
- Suction line
- No model-specific value is published on the current Carrier consumer listing
- Line connection type
- not published
- Precharged length
- not published
- Included line-set length
- Professional installations use separately selected line sets
- Maximum line-set length
- No model-specific value is published on the current Carrier consumer listing
- Max line set per indoor
- not published
- Max height between indoor units
- not published
- Indoor dimensions
- No model-specific value is published on the current Carrier consumer listing
- Outdoor dimensions
- No model-specific value is published on the current Carrier consumer listing
- Indoor weight
- No model-specific value is published on the current Carrier consumer listing
- Outdoor weight
- No model-specific value is published on the current Carrier consumer listing
- Drain size
- not published
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- Line sets
- Line-set covers
Frequently asked questions
- Can I install the Carrier Infinity 27 33,000 BTU R-454B 208/230V (45MAHAQ33XA3 / 37MAHAQ33AA3) myself, or do I need a pro?
- Carrier Infinity 27 33,000 BTU R-454B 208/230V (45MAHAQ33XA3 / 37MAHAQ33AA3) is built for professional installation: the line set must be flared, evacuated, and charged, which requires EPA-certified refrigerant handling. Installing it outside the manufacturer's requirements can void the warranty, so budget for a qualified HVAC installer.
- Will the Carrier Infinity 27 33,000 BTU R-454B 208/230V (45MAHAQ33XA3 / 37MAHAQ33AA3) keep heating in a cold winter?
- The manufacturer publishes 35,000 BTU/h of heating output at 5F. Certified heating efficiency is 10.5 HSPF2. Match those numbers against your climate's design temperature - in cold regions, output at 5F matters far more than the nameplate capacity measured at 47F.
- What electrical circuit does the Carrier Infinity 27 33,000 BTU R-454B 208/230V (45MAHAQ33XA3 / 37MAHAQ33AA3) need?
- Published electrical requirements: 230 V voltage, No model-specific value is published on the current Carrier consumer listing minimum circuit ampacity, and No model-specific value is published on the current Carrier consumer listing maximum breaker or fuse sizing. Confirm the final circuit against the unit nameplate and local code with a licensed electrician.
- How far can the outdoor unit be from the indoor head?
- The published maximum line-set length is No model-specific value is published on the current Carrier consumer listing. Longer runs than the included set allows typically mean added refrigerant and a pro visit, so measure the planned routing before ordering.
- What warranty does the Carrier Infinity 27 33,000 BTU R-454B 208/230V (45MAHAQ33XA3 / 37MAHAQ33AA3) carry?
- The manufacturer publishes these warranty tiers: Standard: 10 yr parts / no separate compressor term (eligible timely registered residential installation). Registration requirements and proof of qualified installation commonly affect coverage, so read the warranty terms before install day.
Data sources
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- Carrier Corporation: Carrier Infinity 27 Mini Split Heat PumpSourced - manufacturer product page
Covers Frequency, Phase, Voltage, Voltage range, Legacy warranty value, Standard compressor warranty status and more
- Air-Conditioning, Heating, and Refrigeration Institute: AHRI Appendix M1 public detail for 37MAHAQ33AA3 / 45MAHAQ33XA3Sourced - AHRI directory
Covers AHRI certification number, performance_spec.cold_climate_designation, Rated cooling capacity, COP at 5F, EER2, Rated heating capacity and more
- ENERGY STAR: ENERGY STAR exact row check for AHRI 215323747Sourced - Energy Star listing
Covers Energy Star status
- HVACDirect: HVACDirect exact Carrier offer for 37MAHAQ33AA3 / 45MAHAQ33XA3Sourced - retailer listing
Covers Retail price
Last updated
Jul 27, 2026